The present application relates to wide band expansion of stereophonic signals as discussed in U.S. Pat. No. 5,091,957 of Anderson et al. The teaching of the '957 patent is expressly incorporated by reference herein. The '957 patent disclosed a wideband expander, and recognized that for practical purposes, satisfactory restoration of an (L−R) audio difference signal companded according to the DBX format can be achieved without spectral expansion. A decoder according to '957 provides a modified fixed deemphasis and wideband expansion of the received compressed L−R audio signal, but does not provide spectral expansion. Additionally, it was further recognized in '957 that the relatively complex RMS detectors of the DBX system can be replaced with simpler, lower cost integrating peak detectors.
It is desirable to design and build television receivers wherein different decoders can be used depending upon model and options.